Initial cell selection is a procedure for a wireless device to determine the presence of a wireless network and find a suitable cell via which to access the network. In the initial cell selection, the wireless device scans a list of possible carrier frequencies of configured operating bands, searches for the cell with the strongest signal strength, finds a cell identification number for the cell with the strongest signal strength, and detects the channel bandwidth and other broadcast information, such as a public land mobile network (PLMN) identification number for that cell. Having found a suitable cell via which to access the network, the wireless device also needs to regularly perform a cell reselection procedure to search for a potentially better cell, which may use a different frequency, via which to access the network. The time required for initial cell selection impacts the end user experience. The time for cell reselection in particular is an important contributing factor to the power consumption of a wireless device.
To speed up the carrier frequency scan, a received signal strength indicator (RSSI) based carrier frequency scan may be employed and the carrier frequencies with strong RSSIs are identified for further cell identification. However, the conventional RSSI scan does not work well for Long Term Evolution/Evolved UMTS Terrestrial Radio Access (LTE/E-UTRA) where the channel bandwidth is unknown a priori; specifically the channel bandwidth can be one of six possible channel bandwidths, i.e. 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz, or 20 MHz. Also, the conventional RSSI scan cannot directly detect the channel bandwidth being used from six possible channel bandwidths.